I have one of the original Snake Charmers. It is a small .410. The Tamer is a little bit bigger. I do carry mine on my ATV, though we don't have poisonous snakes here. In fact I'm not really sure what it is good for other than fooling around with.
You can buy those survival stocks and turn just about any H&R/NEF single shot into a similar type shotgun or rifle.
The stock on mine is really short and basically used as a pistol It holds it's shells inside the buttplate of the stock.